docs: def _parse_ranking(self, field, boxscore):
          """
          Parse each team's rank if applicable.
  
          Retrieve the team's rank according to the rankings published each week.
          The ranking for the week is only located in the scores section at
          the top of the page and not in the actual boxscore information. The
          rank is after the team name inside a parenthesis with a special
          'pollrank' attribute. If this is not in the team's boxscore
          information, the team is assumed to not have a rank and will return a
          value of None.
  
          Parameters
          ----------
          field : string
              The name of the attribute to parse.
          boxscore : PyQuery object
              A PyQuery obejct containing all of the HTML data from the boxscore.
  
          Returns
          -------
          int
              An int representing the team's ranking or None if the team is not
              ranked.
          """
          ranking = None
          index = BOXSCORE_ELEMENT_INDEX[field]
          teams_boxscore = boxscore(BOXSCORE_SCHEME[field])
          # Occasionally, the list of boxscores for the day won't be saved on the
          # page. If that's the case, return the default ranking.
          if str(teams_boxscore) == '':
              return ranking
          team = pq(teams_boxscore[index])
          if 'pollrank' in str(team):
              rank_str = re.findall(r'\(\d+\)', str(team))
              if len(rank_str) == 1:
                  ranking = int(rank_str[0].replace('(', '').replace(')', ''))
          return ranking